Improvement in the therapy of fungus infections: a. Screening for antifungal agents using yeast and other fungi with amphotericin B and polymyxin B. b. Screening for antifungal synergism by using agents in combination with amphotericin B and polymyxin B. c. The successful agents in "a" and "b" will be tested in vivo. Adjuvant Properties of Amphotericin B: The adjuvant properties of amphotericin B will be characterized and the effects of amphotericin B on the stimulation of host resistance to infections and tumors will be studied. Molecular and biochemical studies on fungi to better understand drug resistance and pathogenesis of infection: a. Mechanism of action of antifungal agents. b. Morphogenesis and the basis for the adaptation of dimorphic fungi to the parasitic form.